The Islamic State released a video Thursday purportedly showing its fighters firing antitank guided missiles at Turkish positions, possibly destroying what appears to be two self-propelled artillery pieces and a tank.

According to the video description, the attack occurred on the Turkey-Syria border. Once a conduit for foreign fighters, Turkey has since tried to limit the illegal traffic of people and equipment flowing into the region after facing pressure from the United States and other Western countries.

Turkish military positions and border towns have been shelled by the extremist group in the past, but a direct attack such as the one in the above video is rare.

In the video, Islamic State fighters use what appears to be either a Russian-designed 9M133 Kornet or 9K155-2 METIS-M antitank guided missile. Fielded in the 1990s, both the METIS and the Kornet operate much like the U.S. TOW missile, but instead of using a wire to direct the missile into the target, they have laser-guided warheads.

The three missiles appear to hit three T-155 self-propelled artillery pieces. The T-155 is a tracked howitzer that has a 155mm gun, much like the U.S. Army’s M109 Paladin. The three vehicles that were attacked appear to have been partially covered by pre-dug positions and berms, indicating they might have been there for some time. It is unclear from the video the extent of the damage incurred from the strikes or whether anyone was killed.

The incident coincides with a surge of Islamic State rocket attacks across the border into Turkey that have killed civilians, sown panic and triggered angry street protests. Worst hit is the small Turkish border town of Kilis, where 18 people have been killed since January, most of them this month.

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Turkish officials sought to play down this attack, however, saying that five mortar shells targeted its military near the border town of Karkamish, adjacent to the Islamic State-held town of Jarablus in northern Syria’s Aleppo province. One caused minor damage to a howitzer, and three landed in an empty field, Ali Yerlikaya, the governor of the Turkish province of Gaziantep, told Turkey’s Hurriyet Daily News. He said there were no casualties. 

Turkish troops along the border returned fire, the governor added. The newspaper quoted sources as saying that 11 Islamic State militants were killed in the retaliatory fire.

The escalating cross-border attacks nonetheless call into question how long Turkey can tolerate the attacks on its territory. The Pentagon announced this week that it would move rocket artillery into Turkish territory to help support local opposition forces fighting across the border in Syria. It is unclear whether the systems will also help Turkish forces defend themselves. 

Liz Sly reported from Beirut.